A low-cost, high-reliability polarization-independent optical waveguide interferometer is proposed which does not bring about any additional job involved in the insertion of a half-wave plate or excess loss of light. The system includes an MPLS network having DS-TE compliant routers and links with available bandwidth between the routers. Cell selection for the user equipment is then controlled based on the primary direction of traffic flow for the user equipment such that selection of the high power base station cell is favored if the primary direction of traffic flow is the downlink direction and selection of the low power base station cell is favored if the primary direction of traffic flow is the uplink direction. Each of the trench capacitors has a trench top oxide that extrudes from a main surface of the semiconductor substrate. A process for preparing aerated, ultra low-density cast-dehydrated detergent bars wherein the air is entrained in the bars after rigidification and shaping the product is also provided.